In this article I’ll discuss the variety of common service related issues in the early HP 4000 series printer family. You may be wondering why I’m focusing on these older printer models. In my opinion, next to the HP 4 and 5 series, the HP 4000 series is one of the best lines of printers ever made. Many of these machines are still in the field and, due to age, some of these problems are becoming more frequent. Because these machines have become “more repairable” over the last year since the price on the parts has drastically dropped and the cost of the toner cartridges have gotten lower, they are some of the cheapest machines to run given the cost per page. So for your customers who are thinking about how they can get the most for their money, these machines offer what they are looking for.
NOTE: Almost all the part numbers listed in this article are for the 4000 series. The 4100 uses different part numbers for the feed rollers, pick up and feed assemblies, and the paper size board is different on some of the models given the extra feed trays. Get the 4100 printer specific part numbers here
Let’s take a look, then, at some of the common errors.
41.5 Printer Error- Media feed error
Several things can cause this issue. The easiest one to check is the feed/separation roller in the tray or inside the cassette cavity. Make sure the rollers are properly clipped into place, especially the tray roller. Sometimes, when cleaning the machine or replacing the printer’s maintenance kit, the roller is pulled out and the new roller is quickly installed without checking to make sure the roller is clicked into place. The roller has to mesh with the black torque limiter and the limiter on the opposite site has to mesh with the metal shaft that the two parts sit on for proper installation.
Second, and the most common problem I see, is the feed assembly (part # RG5-2561) behind the tray 1 pick up assembly. I’ve made it a spare part to carry around in my car stock. There really isn’t an easy way to troubleshoot this other than to make sure the feed/separation rollers are properly installed and try to print from tray 1 to see if the error happens from that tray. If the error doesn’t happen from tray 1 then your best bet is to replace the feed assembly.
One flag sits in the middle of the registration assembly and the other is located behind the feed assembly discussed above. Both parts are on the same assembly but replacement involves removal of the engine board.
The next thing would be to check the paper in the tray. Sometimes when users add paper the bottom sheet curls up between the paper and the front of the machine causing the remaining paper in the tray to not lift properly as the paper supply is removed. If the paper seems fine then turn the machine around and remove the dust cover if it has one. This allows us, with a flashlight, to watch the pick up assembly as it goes through its process. If while watching you notice that the paper feeds up an inch or two then moves back a half-inch before feeding into the machine all the way we know we probably have a problem with the black torque limiter in the cassette tray. You can either replace the limiter (part# RB1-8974)
with a new one or pull it apart and remove a little of the metal filings inside the limiter. Don’t remove all the filings. Reinstall and watch again from the back. The paper should be moving correctly.
Additionally, watch the four half-moon pick up rollers (part# for the 4100 RB1-8957) (part# for the 4000 RB1-8865)
and make sure they are only moving when needed and getting back to the home position. There is a spring on the left side of the pick up roller shaft
that pulls the pick up shaft to make sure the half-moon rollers are facing up when the machine is not functioning. If you notice that the feed rollers are facing down at a ready state, make sure the spring is attached.
On the right side is the drive coupler, which is shaped like a black plastic dumbbell (part# RB1-8877).
Make sure its in place and not cracked. When this HP printer model was first introduced I was replacing two or three of these a week until HP made some changes to the paper tray to limit the amount of paper that could be installed.
The last thing to do would be replace the pick up assembly
Tray 2, 250 sheet (part# RG5-2672); Tray 3, 250 sheet (part# RG5-2684); Tray 3, 500 sheet (part# RG5-2672); Tray 2 for the 4100 (part# RG5-5277). I just replaced one the other day that was jamming every 100 to 200 pages to find it had a broken tooth on one of the drive gear arms.
13.20 Paper Jam Error
This is the most common error that I get calls on for this printer model. If a maintenance kit or fuser was installed right before getting the error then pull the fuser out and check the sensor on the left side of the fuser.
It’s possible that the sensor wasn’t fully seated or got jostled during shipping so it sits at an angle and the sensor flag will periodically catch on it.
Often, though, it’s a paper jam in the front of the machine. Usually a piece of paper gets stuck in the front and when the customer tries to get it out some of the paper gets left in the machine, unreachable. When you arrive on-site, if the paper is not stuck on the sensor flag, it might start up and appear to be running OK until you print and the paper gets jammed in the front of the machine.
Sometimes, pushing through a more durable material like a file folder cut in half, will push the rest of the paper out. To do that, remove the cassette tray and toner. Then take the file folder and slowly push it up from the bottom of the machine to the top. Do not attempt to do this from the top to bottom or you could break the feed sensor flag.
Another option is to take the MP pick up assembly
off and clean out the paper path to make sure all the debris is cleared out. I have found that customers try to remove the jam themselves with whatever is lying around the office so this process also gives me a chance to check for nicks on the plastic in the feed path which I can then file down, if needed, so the problem does not recur.
Paper Jam: Miscellaneous
Another thing that can cause odd paper jams which can be hard to detect is a worn solenoid dampener.
As described above in the 13.1 Paper Jam Error section, turn the machine around and watch the pick up process. Watch the four half-moon pick up rollers and make sure they are only moving when needed. The pick up rollers should only move once per sheet of paper so if they rotate a few times as one piece of paper is being fed then most likely the solenoid arm is sticking and indicates that the solenoid dampener is getting worn out.
The dampener is a foam-like material that reduces noise as the solenoid arm contacts the rest of the solenoid. When the foam wears out the sticky glue that once held the dampener in place causes the arm to stick to the solenoid causing the pick up rollers to feed multiple times before stopping. If you see this happening you have a few options; either replace the material and clean the solenoid arm to remove the glue debris, or purchase a new or reconditioned solenoid pick up assembly (part# RG5-2672)
as the solenoid is not sold separately.
Tray 1 Load Letter or 41.3 Error
Usually the 41.3 error occurs when trying to force paper through by pressing the GO button. Sometimes opening and closing the cassette fixes the problem – for awhile.
When the 41.3 error occurs, the first thing to check is the rear paper stop in the cassette tray.
The paper stop controls the paper size settings so if using letter sized paper, make sure the stop is all the way forward in the cassette. If that looks fine then print off a config page using the MP tray if necessary. On the config page, in the second column on the left at the bottom is the paper size settings. If you notice that the tray 2 settings don’t match the paper size in the tray then most likely the paper size control board is going out. The control board is in the back of the cassette tray cavity. It’s covered by a black piece of plastic with three metal leaf springs sticking out.
On the cassette tray, you’ll notice two or three white plastic fingers that coincide with the leaf springs in the machine. If you move the paper stop to a different position the fingers move into different positions. Over time the switches on the board wear out causing the machine to misread the size settings on the tray. Replacement of the board (part# RG5-2685) will be necessary to resolve the issue.
Another thing I like to do when servicing any HP 4000 printer (4100’s have a different design), is to push the paper stop back exposing the front two slots in the bottom metal plate. Using a screwdriver, pry the back of the slots up slightly then move the paper stop back into position. Over time the bottom of the stop wears out causing the stop to want to move back. This is most common when your customer routinely loads a whole ream of paper. The weight of the paper or slamming the cassette closed causes the stop to slide back. By prying the notches up slightly you will notice it takes much more effort to move the stop back.
Multiple Feeding from the MP Tray
When servicing any HP 4000 printer I always check the MP tray. Originally the printers were equipped with a separation pad that was all one unit. The pad was part of the holder. Within a year or two the separation pad was updated and the new separation pad assemblies came with the holder and a pad that is easily removed without removal of the whole assembly. If I see the old one-piece pad still installed I always ask the customer if they use the MP tray and notice multiple feeding. Typically, if answered yes, they will add that they can only feed one at a time because of it grabbing five or six sheets at a time. So replacement will be necessary (part# RG5-5281). Replacement is easy and the customer will appreciate that you are going the extra step in making sure you are checking the whole printer out.
The 4100 series comes with the updated part so if multiple feeding is occurring, only the pad will have to be replaced (part# RF5-3086) I usually keep several updated separation pad assemblies (part# RF5-5281) in my car stock.
Noises and Squeaks
The main noise I hear from the HP 4000 LaserJet printers comes from the MP tray clutch assembly, which sounds like a gear moving roughly inside the front of the machine. Typically, by opening the MP tray door, you can hold onto the feed roller and feel it. By gently moving the feed roller slightly in one direction or another you can change the noise. If the noise is really bad you can even watch the feed roller rattle in place. I usually just remove the MP pick up assembly, disassemble the clutch, clean it out, lubricate it slightly, then reinstall. I’ve heard of people just slightly spraying some oil into the pick up assembly without removal but I prefer to take it out and rebuild it to make sure it doesn’t happen again.
Another noise that I’ve been getting some complaints about is a loud clicking noise when it picks up the paper, which is caused by the pick up solenoid. Again, the only thing you can do there is replace the solenoid pick up assembly (part# RH7-2672) or refurbish the solenoid if you can find a suitable material to replace the worn dampener.
Squeaks usually come in two places. The first is the transfer roller. Originally, the metal shafts on either end were not lubricated. Over time they start to squeak. Whenever servicing any machine I remove the transfer roller, clean the shafts, and apply a little lubrication. Grease should be used here as oil will drift into the roller and get absorbed causing imaging problems on the sides. Most new transfer rollers, especially in the 4200 series, have grease on them….a nice, black grease that tends to get on your hands and everything you touch for the next five minutes, like your nice pants. Ugh!
The second squeak I hear a lot comes from the exit roller shaft. Sitting on top of the shaft is two black guides.
I typically remove the top cover and top of the exit assembly, then remove the guides and place a drop of oil were the guides come into contact with the metal shaft. Grease is too thick here. Placing grease on the shaft will cause the guides to want to move up when the machine is running causing a rattling noise.
Control Panel Buttons
The control panel buttons like to fail on the HP 4000 printer. In most cases the customer doesn’t say anything but when you go to print off a config page you soon realize the issue. It’s a pretty easy fix; just remove the control panel and disassemble it down to the button contact pad.
The contacts have a silver coating over them. My guess is it was originally designed to prevent rusting but overtime it prevented the contacts from making proper contact with the board. I usually just take a screwdriver or spring hook and slightly scratch away at the coating exposing the metal beneath, reassemble, and put the control panel back in place. I’ve been doing them for about 12 years now and I know I still service some of them and never had an issue after taking some of the coating off.
Light Print on Left Side
Light print on the left side is usually due to dirty optics in the Laser/Scanner assembly. First try a new cartridge but if that fails remove the top cover and exit assembly, and clean out the optics with a cotton applicator focusing mainly on the mirrors on the scanner motor and the front mirror sitting at an angle. The motor turns like a fan and you will notice on one side dust likes to build up. Gentle cleaning is the key here so you don’t scratch the mirrors on the motor.
Image Not Properly Fused on the Sides
Remove the fuser and check for discoloration on the fuser film sides. Printing off a config page typically shows you what you’re looking for. If the fuser film is worn the boarder lines on the side will be distorted and will trail off the page. Replace the fuser.
We’ve covered a lot of information here. Most of these repairs are easily done within the one hour time frame allowed per call and a lot of them can be done without purchasing parts. On just about all the HP 4000’s I work on there are more issues than what is reported. By reading this article and understanding what to look for you can positively affect the way a customer views your company. Our company is small so lots of my business comes from unsatisfied customers dealing with larger service companies who focus more on the number of calls one can complete in a day. While I agree that’s important it’s also important that a customer believes you are looking out for their best interest. When you do more than what is expected they take note and put you at the forefront when future calls are needed. They understand they are getting someone with a full understanding of the equipment they are servicing and will take the time to make sure the machine is functioning the way it’s meant to be. Not just fixing one problem to have another appear a few months later.
Kevin Gumpp is a certified printer technician and freelance writer for Market Point. If you have a question for Kevin regarding this topic or have any other printer repair related questions or topics you would like more information on, please send an email to email@example.com.